I don't want to test my own app. I just want to install wordpress for ios.
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metal-gear-solidJan 3 '11 at 19:21

@metal-gear-solid: If you want to run it in the simulator, I think you will need to download the sources and compile them with Xcode. I don't think you can install an app from the App Store in the simulator. You will probably get better answers on the Apple Stack Exchange or the main Stack Overflow site.
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Jan FabryJan 3 '11 at 19:38